IT’S 4.03am on Friday July 8.

Adrenalin is running high at the Manchester Central convention complex. It has kept the sleep-deprived campaigners of both pro and anti-EU camps energised through the wee small hours.

Three regional recounts have only added to the tension. An exit poll has handed the vote on Britain’s membership of the European Union narrowly to the Yes camp.

But tensions are high and, given the past performances of exit polls, no one is quite sure what the final outcome will be. The regional results, which have flashed up one by one on the large electronic screen, have only confirmed that the contest is too close to call.

Herald View: Battles lines being drawn for the EU fight ahead  

Finally, Jenny Watson, the Chief Counting Officer, nods to her colleagues, takes a deep breath and strides onto the illuminated stage. There is a sea of expectant faces and a nation is holding its breath. So too is Europe.

Gripping a single piece of paper, the chairwoman of the Electoral Commission announces the landmark result: 52.1 per cent to 47.9 per cent. The United Kingdom has voted to leave the European Union.

An explosion of emotion erupts in the convention hall. The cheers, smiling faces and cries of jubilation from the anti-EU camp are mirrored in their scale by the groans, closed eyes and tears of defeat by the pro-EU camp.

Union flags are waved in triumph by the “outers” but there is a twist to the tale. While the UK has voted narrowly to leave the EU, Scotland has voted, 55 per cent to 45 per cent, to stay. In Edinburgh, there is talk of “unfinished business”.

The markets take a hit. The FTSE Index plunges seven per cent in early trading but by the end of the day is down just 160 points. Turbulence in the weeks and months ahead is guaranteed.

The in/out campaign itself was marked by recrimination and bitterness.

The wound that the Conservative Party had for so long been able to keep closed burst open after David Cameron emerged, following months of delicate talks with his European counterparts, claiming victory on his bid to reform Britain’s relationship with Brussels.

But the package fell well short of what the Eurosceptics had wanted. It was “an insult to the British people”, declared John Redwood, the Eurosceptic former Cabinet minister.

The PM’s attempt to get a four-year ban on in-work benefits for migrants crumbled as member state after member state objected. The compromise of an emergency brake on migration, hailed by the Prime Minister as a political triumph in a club of 28 nations, was deemed an embarrassing failure by his opponents.

Five Cabinet ministers had threatened to resign if their leader did not allow a free vote. Like Jeremy Corbyn a few months earlier on the Syria issue, Mr Cameron was faced with a dilemma, particularly given the seniority of those who were intent on voting No; these included Theresa May, Michael Gove, Chris Grayling and Iain Duncan Smith.

In the end, like the Labour leader, the PM allowed Cabinet members to campaign on either side. But all this did was to lift the lid on bitter wrangling among senior Tories. Damage had been done to the Conservative brand and, whatever the outcome, it was hard to see how Mr Cameron, if he won, was going to steady the Tory ship.

But he had lost. The issue of Europe which had contributed to the defeat of John Major and eventually saw off Margaret Thatcher had now claimed another Conservative scalp.

Within hours of the No vote, the PM, almost two years after savouring the victory of another No vote in Scotland, is again on the street outside No 10, tasting a different political dish.

He announces to the nation that he respects the British public’s verdict and will, after a short period of transition, stand down.

Manoeuvrings within his party have already begun. Ms May is lauded by her colleagues as the true voice of Britain. She quickly gets support for a leadership bid by former London mayor Boris Johnson.

Meantime, George Osborne, the heir apparent to Mr Cameron, gives a brief comment of disappointment yet already has a keynote speech planned for the following day; his campaign is ready to go.

After his brief Downing Street statement, the Tory leader turns and heads back through the famous black door; he cuts a lonely, dejected figure.

In contrast, a beaming and ebullient Nigel Farage is surrounded by a media circus. The location is Fred’s Caf, a greasy spoon in the heart of Manchester. The Ukip leader is downing a fried breakfast.

Bob, the landlord of the pub next door, arrives and plonks a pint of bitter on his table. “Never too late to celebrate,” croaks Nige as the cameras flash. “We’ve just saved Britain £12 billion a year.” But whither Mr Farage and Ukip now they have their triumph?

Back in a different part of London Jeremy Corbyn, wounded by Labour’s dreadful performances in the May elections north and south of the border, can at last indulge in a bit of schadenfreude but the respite will only be brief given the depth of divisions within Her Majesty’s Opposition. Those tectonic plates are beginning to shift again.

Over in the Belgian capital, shock waves are still reverberating at Britain’s unexpected Non. Jean-Claude Juncker, the European Commission President, who launched a last-minute appeal for Britain to stay with the European family, is in front of the cameras, admitting that this is “a dark day for the European Union”. To lose Greece would have been one thing but the United Kingdom?

In Washington, President Barack Obama has already telephoned Mr Cameron to offer his commiserations but leaves the defeated PM in no doubt that Brexit will have consequences for the(not so) special relationship.

In Edinburgh meantime, Nicola Sturgeon has called an emergency Cabinet meeting for 10am. Another media circus is gathered outside Bute House, bathed in early summer sunshine.

At the SNP conference the previous autumn, the First Minister noted how having a second independence referendum if the UK voted No to the EU but Scotland voted Yes was “probably unstoppable”.

But even with another landslide victory at the May Holyrood elections, there is still nervousness about calling a snap second independence poll because, for some, there remains a doubt about whether the pro-independence camp could win it.

The referendum in 2014 showed that translating support for the SNP into support for independence was not automatic; nor, some Nationalist figures fear, is translating a No vote to the EU into a Yes vote for independence.

The Bute House Cabinet meeting has followed a range of intense early morning phonecalls between Ms Sturgeon and her senior colleagues.

Alex Salmond, the FM’s predecessor, has been the most passionate, demanding his colleague announce a second referendum in September. “Do it now,” he implores his colleague. “Scotland is ready.”

Already in Glasgow’s George Square, the saltires are swirling as Yes campaigners call for another say on Scotland’s future.

The Scottish Government’s Cabinet meeting drags on. Eleven o’clock comes and goes.

It is almost noon when the SNP leader appears on the steps of Bute House, surrounded by her colleagues, to announce that she will be recommending a second independence poll. Scotland, she declares, has spoken. Its wishes need to be recognised. A referendum Bill will be quickly rushed through Holyrood. Westminster, she insists, must give its consent; it has no choice.

Yet neither Mr Osborne nor Mrs May are minded to rush into another battle for the Union. They have a more immediate fight to contemplate; one for the Tory crown and the keys to Downing Street.

But the Nationalists are eager to re-enter the ring. Westminster only has two weeks before its summer recess and the phalanx of SNP MPs are repeatedly pressing in the Commons chamber for the UK Government to give its consent for a second referendum.

Mr Salmond is indefatigable. He voices the threat that Scotland will hold a plebiscite anyway; with or without Westminster’s consent. Scotland, he declares, not London will decide its future.

But the Scottish question is just one of an array of unintended consequences unleashed by Mr Cameron’s lost gamble on Europe.

Ahead lie months if not years of UK Government’s negotiations not just with Brussels in decoupling from the Union but with the 27 former partners.

Britain’s relationship with America and, indeed, the rest of the world has been changed with the outcome of the EU referendum.

And as the UK contemplates a second Scottish independence poll and begins the painful process of exiting the EU, within 48 hours of the referendum result, Mr Salmond, never one to let a political opportunity slip, is in Brussels giving a speech and making the point that while the European Union may be losing one family member, it can expect soon to be gaining another.

By the end of August, Mr Cameron, accompanied by Samantha, is climbing into the back of a limousine to leave Downing Street for the last time.

As he joins the pantheon of ex-leaders, the words of Enoch Powell reverberate in his head: “All political lives, unless they are cut off in midstream at a happy juncture, end in failure, because that is the nature of politics and of human affairs.” So it is.